In North America we are seeing more and more ATB's, Articulated Tug Barge. Because they are secured to each other by one system or another, such as BLUDWORTH-COOK SYSTEM, they are neither Tug nor Barge nor Tanker. Is it possible to have a category for these type of units?

Allo, PaulThose things are so ugly that they do not need a special category, nobody would give them a second look anyway. The Great Lakes where an extremely beautiful place to watch vessels go by and I was there, around 1965 to 1970 when they had all those old bulk freighters steamers.